CheckStatement.cpp

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// Copyright (c) 2008 Roberto Raggi <roberto.raggi@gmail.com>
//
// Permission is hereby granted, free of charge, to any person obtaining a copy
// of this software and associated documentation files (the "Software"), to deal
// in the Software without restriction, including without limitation the rights
// to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
// copies of the Software, and to permit persons to whom the Software is
// furnished to do so, subject to the following conditions:
//
// The above copyright notice and this permission notice shall be included in
// all copies or substantial portions of the Software.
//
// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
// OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
// THE SOFTWARE.

#include "CheckStatement.h"
#include "Semantic.h"
#include "AST.h"
#include "TranslationUnit.h"
#include "Scope.h"
#include "CoreTypes.h"
#include "Control.h"
#include "Symbols.h"
#include "Names.h"
#include "Literals.h"
#include <string>

using namespace CPlusPlus;

CheckStatement::CheckStatement(Semantic *semantic)
    : SemanticCheck(semantic),
      _statement(0),
      _scope(0)
{ }

CheckStatement::~CheckStatement()
{ }

FullySpecifiedType CheckStatement::check(StatementAST *statement, Scope *scope)
{
    FullySpecifiedType previousExprType = switchExprType(FullySpecifiedType());
    Scope *previousScope = switchScope(scope);
    StatementAST *previousStatement = switchStatement(statement);
    accept(statement);
    (void) switchStatement(previousStatement);
    (void) switchScope(previousScope);
    return switchExprType(previousExprType);
}

FullySpecifiedType CheckStatement::switchExprType(const FullySpecifiedType &type)
{
    const FullySpecifiedType &previousExprType = _exprType;
    _exprType = type;
    return previousExprType;
}

StatementAST *CheckStatement::switchStatement(StatementAST *statement)
{
    StatementAST *previousStatement = _statement;
    _statement = statement;
    return previousStatement;
}

Scope *CheckStatement::switchScope(Scope *scope)
{
    Scope *previousScope = _scope;
    _scope = scope;
    return previousScope;
}

bool CheckStatement::visit(CaseStatementAST *ast)
{
    (void) semantic()->check(ast->expression, _scope);
    _exprType = semantic()->check(ast->statement, _scope);
    return false;
}

bool CheckStatement::visit(CompoundStatementAST *ast)
{
    Block *block = control()->newBlock(ast->lbrace_token);
    block->setStartOffset(tokenAt(ast->firstToken()).offset);
    block->setEndOffset(tokenAt(ast->lastToken() - 1).end());
    ast->symbol = block;
    _scope->enterSymbol(block);
    Scope *previousScope = switchScope(block->members());
    StatementAST *previousStatement = 0;
    for (StatementListAST *it = ast->statement_list; it; it = it->next) {
        StatementAST *statement = it->value;
        _exprType = semantic()->check(statement, _scope);

        if (statement && previousStatement) {
            ExpressionStatementAST *expressionStatement = statement->asExpressionStatement();
            CompoundStatementAST *compoundStatement = previousStatement->asCompoundStatement();
            if (expressionStatement && ! expressionStatement->expression && compoundStatement && compoundStatement->rbrace_token)
                translationUnit()->warning(compoundStatement->rbrace_token, "unnecessary semicolon after block");
        }

        previousStatement = statement;
    }
    (void) switchScope(previousScope);
    return false;
}

bool CheckStatement::visit(DeclarationStatementAST *ast)
{
    semantic()->check(ast->declaration, _scope);
    _exprType = FullySpecifiedType();
    return false;
}

bool CheckStatement::visit(DoStatementAST *ast)
{
    semantic()->check(ast->statement, _scope);
    (void) semantic()->check(ast->expression, _scope);
    _exprType = FullySpecifiedType();
    return false;
}

bool CheckStatement::visit(ExpressionOrDeclarationStatementAST *ast)
{
//    translationUnit()->warning(ast->firstToken(),
//                               "ambiguous expression or declaration statement");

    semantic()->check(ast->declaration, _scope);
    _exprType = semantic()->check(ast->expression, _scope);

    return false;
}

bool CheckStatement::visit(ExpressionStatementAST *ast)
{
    _exprType = semantic()->check(ast->expression, _scope);
    return false;
}

bool CheckStatement::forEachFastEnum(unsigned firstToken,
                                     unsigned lastToken,
                                     SpecifierListAST *type_specifier_list,
                                     DeclaratorAST *declarator,
                                     ExpressionAST *initializer,
                                     ExpressionAST *expression,
                                     StatementAST *statement,
                                     Block *&symbol)
{
    Block *block = control()->newBlock(firstToken);
    block->setStartOffset(tokenAt(firstToken).offset);
    block->setEndOffset(tokenAt(lastToken - 1).end());
    symbol = block;
    _scope->enterSymbol(block);
    Scope *previousScope = switchScope(block->members());
    if (type_specifier_list && declarator) {
        FullySpecifiedType ty = semantic()->check(type_specifier_list, _scope);
        const Name *name = 0;
        ty = semantic()->check(declarator, ty, _scope, &name);
        unsigned location = declarator->firstToken();
        if (CoreDeclaratorAST *core_declarator = declarator->core_declarator)
            location = core_declarator->firstToken();
        Declaration *decl = control()->newDeclaration(location, name);
        decl->setType(ty);
        _scope->enterSymbol(decl);
    } else {
        (void) semantic()->check(initializer, _scope);
    }

    (void) semantic()->check(expression, _scope);
    semantic()->check(statement, _scope);
    (void) switchScope(previousScope);
    _exprType = FullySpecifiedType();
    return false;
}

bool CheckStatement::visit(ForeachStatementAST *ast)
{
    return forEachFastEnum(ast->firstToken(),
                           ast->lastToken(),
                           ast->type_specifier_list,
                           ast->declarator,
                           ast->initializer,
                           ast->expression,
                           ast->statement,
                           ast->symbol);
}

bool CheckStatement::visit(ObjCFastEnumerationAST *ast)
{
    return forEachFastEnum(ast->firstToken(),
                           ast->lastToken(),
                           ast->type_specifier_list,
                           ast->declarator,
                           ast->initializer,
                           ast->fast_enumeratable_expression,
                           ast->statement,
                           ast->symbol);
}

bool CheckStatement::visit(ForStatementAST *ast)
{
    Block *block = control()->newBlock(ast->for_token);
    block->setStartOffset(tokenAt(ast->firstToken()).offset);
    block->setEndOffset(tokenAt(ast->lastToken() - 1).end());
    ast->symbol = block;
    _scope->enterSymbol(block);
    Scope *previousScope = switchScope(block->members());
    semantic()->check(ast->initializer, _scope);
    FullySpecifiedType condTy = semantic()->check(ast->condition, _scope);
    FullySpecifiedType exprTy = semantic()->check(ast->expression, _scope);
    semantic()->check(ast->statement, _scope);
    (void) switchScope(previousScope);
    _exprType = FullySpecifiedType();
    return false;
}

bool CheckStatement::visit(IfStatementAST *ast)
{
    Block *block = control()->newBlock(ast->if_token);
    block->setStartOffset(tokenAt(ast->firstToken()).offset);
    block->setEndOffset(tokenAt(ast->lastToken() - 1).end());
    ast->symbol = block;
    _scope->enterSymbol(block);
    Scope *previousScope = switchScope(block->members());
    FullySpecifiedType exprTy = semantic()->check(ast->condition, _scope);
    semantic()->check(ast->statement, _scope);
    semantic()->check(ast->else_statement, _scope);
    (void) switchScope(previousScope);
    _exprType = FullySpecifiedType();
    return false;
}

bool CheckStatement::visit(LabeledStatementAST *ast)
{
    semantic()->check(ast->statement, _scope);
    _exprType = FullySpecifiedType();
    return false;
}

bool CheckStatement::visit(BreakStatementAST *)
{
    _exprType = FullySpecifiedType();
    return false;
}

bool CheckStatement::visit(ContinueStatementAST *)
{
    _exprType = FullySpecifiedType();
    return false;
}

bool CheckStatement::visit(GotoStatementAST *)
{
    _exprType = FullySpecifiedType();
    return false;
}

bool CheckStatement::visit(ReturnStatementAST *ast)
{
    _exprType = semantic()->check(ast->expression, _scope);
    return false;
}

bool CheckStatement::visit(SwitchStatementAST *ast)
{
    Block *block = control()->newBlock(ast->switch_token);
    block->setStartOffset(tokenAt(ast->firstToken()).offset);
    block->setEndOffset(tokenAt(ast->lastToken() - 1).end());
    ast->symbol = block;
    _scope->enterSymbol(block);
    Scope *previousScope = switchScope(block->members());
    FullySpecifiedType condTy = semantic()->check(ast->condition, _scope);
    semantic()->check(ast->statement, _scope);
    (void) switchScope(previousScope);
    _exprType = FullySpecifiedType();
    return false;
}

bool CheckStatement::visit(TryBlockStatementAST *ast)
{
    semantic()->check(ast->statement, _scope);
    for (CatchClauseListAST *it = ast->catch_clause_list; it; it = it->next) {
        semantic()->check(it->value, _scope);
    }
    _exprType = FullySpecifiedType();
    return false;
}

bool CheckStatement::visit(CatchClauseAST *ast)
{
    Block *block = control()->newBlock(ast->catch_token);
    block->setStartOffset(tokenAt(ast->firstToken()).offset);
    block->setEndOffset(tokenAt(ast->lastToken() - 1).end());
    ast->symbol = block;
    _scope->enterSymbol(block);
    Scope *previousScope = switchScope(block->members());
    semantic()->check(ast->exception_declaration, _scope);
    semantic()->check(ast->statement, _scope);
    (void) switchScope(previousScope);
    _exprType = FullySpecifiedType();
    return false;
}

bool CheckStatement::visit(WhileStatementAST *ast)
{
    Block *block = control()->newBlock(ast->while_token);
    block->setStartOffset(tokenAt(ast->firstToken()).offset);
    block->setEndOffset(tokenAt(ast->lastToken() - 1).end());
    ast->symbol = block;
    _scope->enterSymbol(block);
    Scope *previousScope = switchScope(block->members());
    FullySpecifiedType condTy = semantic()->check(ast->condition, _scope);
    semantic()->check(ast->statement, _scope);
    (void) switchScope(previousScope);
    _exprType = FullySpecifiedType();
    return false;
}

bool CheckStatement::visit(QtMemberDeclarationAST *ast)
{
    const Name *name = 0;

    if (tokenKind(ast->q_token) == T_Q_D)
        name = control()->nameId(control()->findOrInsertIdentifier("d"));
    else
        name = control()->nameId(control()->findOrInsertIdentifier("q"));

    FullySpecifiedType declTy = semantic()->check(ast->type_id, _scope);

    if (tokenKind(ast->q_token) == T_Q_D) {
        if (NamedType *namedTy = declTy->asNamedType()) {
            if (const NameId *nameId = namedTy->name()->asNameId()) {
                std::string privateClass;
                privateClass += nameId->identifier()->chars();
                privateClass += "Private";

                const Name *privName = control()->nameId(control()->findOrInsertIdentifier(privateClass.c_str(),
                                                                                           privateClass.size()));
                declTy.setType(control()->namedType(privName));
            }
        }
    }

    Declaration *symbol = control()->newDeclaration(/*generated*/ 0, name);
    symbol->setType(control()->pointerType(declTy));

    _scope->enterSymbol(symbol);
    _exprType = FullySpecifiedType();
    return false;
}